BTX is the most important component of SES, BTX stands for Baseboard Technology eXtended which is similar to ETX for Embedded Technology eXtended. BTX is an EBX size baseboard with patented design. BTX consists of 5 parts, first is the ETX connector second is the on-board specific function , third is the PC/104 bus extension , 4 th is the PCI bus extension the last is the off-the-shelf PC connector on the front. Please refer to the following figure.